An image-taking apparatus is disclosed which can achieve an appropriate AF
control regardless of a zoom magnification. The image-taking apparatus
has an image pickup element which photoelectrically converts an image of
an object formed by an image-taking optical system including a focusing
lens, and a signal processing circuit which produces an image signal
based on an output signal from the image pickup element and has an
electronic zoom function of electrically processing a part of the image
signal to produce an enlarged output image. The image-taking apparatus
also has a detection unit which detects a defocus amount between two
image of the object, and a focus control circuit which controls a drive
of the focusing lens in a first control method based on the output signal
from the image pickup element and a second control method based on an
output signal from the detection unit.